This program project brings together a consortium of investigators representing biochemistry, molecular biology, cell biology, pathology, medicine, hematology, oncology, rheumatology and nephrology who, in addition to disciplinary expertise, are established researchers in the field of neutrophil biology and pathophysiology. The proposal takes the PMN membrane as its theme and presents four specific projects concerning the genomic structure of an important neutrophil adhesion protein, Phospholipid metabolism in PM membrane signal transduction, the effects of PMN membrane lipid modification on PM function, biochemistry and on inflammation in vivo, and the interface between the PMN membrane and the actin cytoskeleton. The scope of the proposed project spans the spectrum between molecular genetics, metabolism and animal pathology. Beyond the particulars of the proposal is the coming together of a critical mass of investigators and a superb advisory group dedicated to the study of nearly all aspects of the neutrophil which dictates that the whole of this project will transcend the sum of its parts.